In Sarajevo on June 28th, 1914, an unknown Bosnian Serb called Gavrilo Princip reached for his gun and pulled the trigger. In doing so, he assassinated Archduke Franz Ferdinand of Austria and his wife, Sophie, in Sarajevo. This action is the starting point of many books, because it was the catalyst that would lead to the outbreak of the First World War only months later.

But for Tim Butcher, this action is not the beginning, but the end. Instead of going forward from this trigger, he goes backwards, asking a range of questions. Who was Princip? Where did he come from? What made a 19-year-old commit such an act? What was he hoping to achieve?

Tracing the life of Gavrilo Princip

He discovers that Princip was born in the remote and tiny village of Obljaj, and travelled to Sarejevo when he was 13 to go to school. Butcher decides to literally follow in Princip’s footsteps. He starts by camping in front of the ruins of Princip’s family house. He ends by standing where Princip stood clutching his weapon as the Archduke passed by.

That in itself would have made an engrossing story – and Tim Butcher is a master story-teller, as anyone who has read Blood River and Chasing the Devil knows perfectly well. But Butcher adds another fascinating layer to the story. This is because he already knows this area, having been sent here as a journalist to cover the Bosnian War in the early 1990s. So he’s aware of the history of the place, the conflicts between Bosnian Serbs, Bosnian Croats and Bosnian Muslims, and the fact that much of the area still contains landmines.

Uncovering buried treasure

On his journey he meets a string of fascinating characters way. They include the Princip family and some fishing mullahs!. Through these and others, Butcher slowly creeps into the skin of Princip and begins to discover answers to the questions he posed. He also uncovers buried treasure: the entire paper record of Princip’s secondary education in Bosnia. It provided clear evidence of the teenage transformation of Princip from country boy to assassin.

A journey back to hell

He is also retracing his own steps that he took in the 1990s, including Sarajevo, where “the avalanche of memory threatened to bury me: road bridges that I remembered having been primed with explosives; the turning to the village where I found three girls with their throats cut; signboards with place names still so charged that my stomach tightened when I read them.”

Butcher’s journey also included “the most emotional hike I have ever made”. This was through the same mountains Princip had crossed, which were intimately connected to the brutal endgame of the Bosnian war … the town of Srebrenica, scene of a horrendous massacre of 8,000 Bosnian Muslims.

The Trigger: The Hunt for Gavrilo Princip, the Assassin who Brought the World to War is an excellent and original read. It’s a combination of fascinating history, personal and often harrowing memories, investigative journalism, helpful explanations of the toxic nature of Balkan nationalism, and a gripping story. This is the story behind what made a 19-year-old pull the trigger that led to one of the deadliest conflicts in the history of the human race.